Using the slogan "One Malaysia. People First. Performance Now," Najib assured the public he was focused on promoting the needs of the Malaysian people through his new governmental post, Bernama said.
"I will be steadfast in my commitment to meet the needs, aspirations and concerns of all Malaysians," Najib, 55, said.
After being sworn in, Najib began his ministerial service by releasing 13 Internal Security Act detainees, along with ending a ban on the Parti Keadilan Rakyat and Pan-Malaysian Islamic Party political groups.
"These decisions are timely as we move to enhance the confidence of our citizens in those entrusted with maintaining peace, law and order, while recognizing the need to remain vigilant of the very real security threats we continue to face as a young nation," Najib said of the ban repeal.
Najib comes into power following the resignation of outgoing Prime Minister Abdullah Ahmad Badawi, who was pressured to resign following a ruling National Front Party defeat in 2008 elections.
Interpol investigating stolen passports on missing flight
Dennis Rodman pledges to end trips to North Korea